The present invention relates to a method for producing liquid hydrocarbons from coal. Liquid hydrocarbons that can be produced according to this method are, inter alia, alkanes, cycloalkanes and aromatics which have a boiling point of 20.degree. to about 350.degree. C. and whose molecules contain 5 to about 30 carbon atoms. Such liquid hydrocarbons are processed primarily into fuels and lubricants and are used as heating oils and chemical raw materials.
It is known that hydrocarbons can be obtained from coal by catalytic hydrogenation. According to the Bergius process, finely ground coal is mixed into a dough with heavy oil or tar and with a molybdenum containing catalyst. The resulting mixture is then hydrogenated with hydrogen at 200 to 300 atmospheres gauge and at 450.degree. to 500.degree. C. The reaction mixture obtained after the hydrogenation is separated by distillation and furnishes gasoline, gas oil and a residue which is again mixed with coal dust and returned to the hydrogenation process. The hydrocarbons produced according to the Bergius process include primarily alkanes and cycloalkanes. See H. Beyer, "Lehrbuch der organischen Chemie", in translation, Organic Chemistry Textbook, published by S. Hirzel Verlag, Leipzig, 1962, pages 63 to 64.